The Gothic defence tower in Oświęcim was erected at the beginning of the 14th century. In the 15th century, it was integrated into the defensive wall. Only the tower remained intact after the castle fire in 1503.In 1512–1513, it was given a superstructure and covered with a shingle roof and a stone ogival portal was placed in the façade, preserved to this day, with a porch on stone corbels. In the 17th century the walls were plastered, the guard's porch was removed and a shingled cupola was installed. The tower lost its defensive functions, but it still housed the prison. By the end of the 18th century it was falling into disrepair, hastened by disastrous floods between 1805 and 1813. In the 19th century it had no roof, and in 1904 a renovation was carried out in order to protect it from further deterioration. In the 1930s, a new wing was built connecting the defence tower to the castle, which destabilised the ground and caused damage to the tower walls. In 1986, it was covered with a new hipped roof. In 1999, the adjacent part of the castle was demolished. At the beginning of the 20th century, conservation work was carried out on the walls.

At first, a plinth of stone blocks was erected up to a height of 1.7 metres above the foundations, work was interrupted, and when work resumed, the high defensive tower was already built of brick on a 10.5-metre square plan. At the base, its walls are about 4 metres thick, and the original entrance was 10 metres above the courtyard with an external wooden staircase leading to it. There was a prison dungeon inside. The tower had two or three storeys connected by an internal staircase. The shingled roof, topped by two copper balls, was changed over time to a tent roof. The entrance from the level of the courtyard was made in the 19th century.